OFFSET
1,1
COMMENTS
Also numbers n such that (47*10^n-11)/9 is prime.
No other terms below 50000.
a(19) > 10^5. - Robert Price, Jul 04 2015
LINKS
FORMULA
a(n) = A101573(n) + 1.
MATHEMATICA
Do[ If[ PrimeQ[(47*10^n - 11)/9], Print[n]], {n, 0, 10000}]
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Robert G. Wilson v, Jan 18 2005
STATUS
approved